The disclosure relates to an electrical assembly.
Electronic control modules that can be arranged on the transmission and in the transmission fluid are used for controlling the transmission in automotive engineering. The control modules can comprise by way of example electrical assemblies such as plug connectors, sensors, actuators, at least one encapsulated control unit (TCU, Transmission Control Unit) and where necessary further components that are fastened to a central carrier and are exposed to the transmission fluid. When components are arranged in the transmission fluid, this places high demands on the technology involved in assembling and connecting the components on the carrier of the electronic control module since the electrical connections must be able to withstand high loadings as a result of temperature changes and withstand transmission fluid that in the worst case scenario contains metal chips. Insert molded lead frames and also rigid circuit boards or flexible circuit boards (so-called flex-foils, FPC) are used in the prior art as carriers in the electrical connection technology.
Insert molded lead frames that comprise metal conductors that are encased by an insulating part that is produced from injection molding represent a particularly robust and tried and tested solution. Free conductor ends of the conductors that are removed from the insulation of the injection molding compound are electrically contacted by male connectors, sensors, actuators or other electrical components of the control module. These electrical components comprise a dedicated component-insulating part, by way of example a sensor housing, and are provided with dedicated electrical conductors. The free conductor ends of these conductors protrude in the form of connection contacts out of the component-insulating part and are electrically connected by means of welding or soldering to the free conductor ends of the electrical conductors of the insert molded lead frame.
The contact site must be protected against aggressive substances and metal chips that are contained in the transmission oil. It is known to arrange the contact site in a receiving chamber that is formed on the insert molded lead frame and is filled with a casting compound after the electrical contact has been produced, in other words by way of example after the free conductor ends have been welded. The potting compound is introduced into the receiving chamber through an open side and by way of example hardens. In order to prevent the potting compound from escaping prior to it hardening, the receiving chamber is embodied as a bath-shaped depression that is closed on at least five sides. A relatively large amount of installation space is required in order to provide a bath-shaped receiving chamber of this type in the insert molded lead frame part so that the carrier of the electronic control module has a specific thickness which is disadvantageous as a result of the higher material costs and the installation situation on the transmission.